Solvent extraction separation of cerium(III) from transition elements with 15-crown-5 with picrate as the counter ion

Abstract

Cerium(III) was quantitatively extracted between pH 6.0 and 8.0 with 0.05 M 15-crown-5 in dichloromethane from 0.01 M picric acid with picrate as the counter ion. Cerium(III) was stripped with 1 M perchloric acid and determined spectrophotometrically at 655 nm as its complex with Arsenazo III. Cerium was separated from a large number of elements. Stepwise extraction of cerium permits its separation from thorium, uranium, scandium, yttrium and strontium. The method was applied to the determination of cerium in monazite sand.